Which of the following parameters In the NR MIB message indicates the time-domain position of
CORESET 0?
D
Explanation:
In 5G NR, the Master Information Block (MIB) message is transmitted on the Physical Broadcast
Channel (PBCH) and contains information that is used by the UEs to synchronize to the cell and
obtain basic system information. The parameters in the NR MIB message that indicate the time-
domain position of CORESET 0 are the least significant four bits of PDCCH-configSIBl.
Which of the following synchronization rasters can be used by a UE during a cell search?
ABC
Explanation:
During a cell search, a UE uses synchronization signals to synchronize to a cell and obtain basic
system information. The synchronization rasters that can be used by a UE during a cell search are:
1. 17.28MHz: This is the synchronization raster that is used for the primary synchronization signal
(PSS) and the secondary synchronization signal (SSS) in 5G NR.
2. 1200kHz: This is the synchronization raster that is used for the primary synchronization signal (PSS)
and the secondary synchronization signal (SSS) in 4G LTE.
3. 1.44MHz: This is the synchronization raster that is used for the cell-specific reference signal (CRS)
in 4G LTE.
Which of the following parameters in core network subscription information restricts the non-GBR
rate for a UE?
A
Explanation:
In 5G Core network, the core network subscription information contains parameters that are used to
manage the resources of a UE.
1. UE-AMBR (UE Aggregate Maximum Bit Rate) : It's the maximum bit rate that is allocated to a UE
for non-guaranteed bit rate (non-GBR) services. It controls the non-GBR rate for a UE.
What is the typical output power of a 64T64R AAU?
D
Explanation:
According to Huawei's 5G AAU Product Brochure, a 64T64R AAU typically has a maximum output
power of 40W. This power is split between the 64 transmitters, so each transmitter has an output
power of 0.625W. The output power of an AAU can be adjusted depending on the specific
requirements. Sources: [1] Huawei. "5G AAU Product Brochure." Huawei, 2019.
https://www.huawei.com/en/products/5g/aau-product.
[2] Wang, X., Ge, X., and Zhang, J. "Analysis
of base station power consumption in 5G ultra-dense networks." IEEE Access, vol. 7, pp. 85812-
85823, 2019.
https://ieeexplore.ieee.org/document/8749683.
When a GPS divider is used, the maximum distance between the GPS antenna and the BBU is
shortened.
A
Explanation:
When a GPS divider is used, the maximum distance between the GPS antenna and the BBU is
shortened. This is because the divider splits the signal from the antenna into multiple signals that
can be distributed to multiple BBUs, thus reducing the distance between the antenna and the BBUs.
Sources: [1] Rymaruk, O., and Kovalenko, I. "GPS signal dividers for cellular base stations." IEEE
Antennas
and
Propagation
Magazine,
vol.
56,
no.
3,
pp.
121-126,
2014.
https://ieeexplore.ieee.org/document/6833669.
[2] Albasri, N., and Al-Naffouri, T.Y. "GPS signal
distribution for a 4G/5G distributed antenna system." IEEE Access, vol. 7, pp. 100371-100382, 2019.
https://ieeexplore.ieee.org/document/8793094.
Which of the following boards do not support 5G?
BD
In CRAN deployment, the one-to-four cascading mode can be used for GPS clock configuration. How
many BBUs at most can a GPS be connected to?
D
Explanation:
In CRAN deployment, the one-to-four cascading mode can be used for GPS clock configuration,
meaning that a single GPS clock can be connected to up to four BBUs at most. Sources: [1] Wang, T.,
Zhao, M., and Li, L. "GPS-based synchronous system solution for CRAN in 5G." In 2019 IEEE
International Conference on Communications Workshops (ICC Workshops), pp. 1-6, 2019.
https://ieeexplore.ieee.org/document/8765054.
[2] Li, L., Zhang, Y., and Chen, F. "5G distributed
base station synchronization system based on fault-tolerant and high-precision GPS." In 2020 IEEE
International Conference on Communications Workshops (ICC Workshops), pp. 1-5, 2020.
https://ieeexplore.ieee.org/document/9160372.
Which of the following are the topologies between a BBU and RF units?
ABD
Explanation:
The following are the common topologies used between a BBU (Baseband Unit) and RF (Radio
Frequency) units:
1. Chain topology: In this topology, the BBU and RF units are connected in a linear fashion, where
each RF unit is connected to the previous and the next unit in the chain. B. Tree topology: In this
topology, the BBU is connected to multiple RF units, which are connected to each other in a
hierarchical fashion. D. Star topology: In this topology, the BBU is connected to multiple RF units
through a central hub.
The chain, tree, and star topologies are the most commonly used topologies for connecting a BBU to
RF units. The ring topology is not commonly used for this type of connection. Sources: [1] Li, Y., Li, Y.,
Li, Y., Li, T., and Li, S. "5G wireless network topology research." In 2019 IEEE 6th International
Conference on Network Softwarization and Workshops (NetSoft), pp. 1-6, 2019.
https://ieeexplore.ieee.org/document/8783934.
[2] Gao, Y., and Wang, Y. "5G ultra-densification cell
architecture research." In 2019 IEEE International Conference on Communications Workshops (ICC
Workshops), pp. 1-5, 2019.
https://ieeexplore.ieee.org/document/8765036.
What Is the maximum number of pRRUs on a CPRI link for RF combination?
B
Explanation:
The maximum number of pRRUs on a CPRI link for RF combination is 16. The CPRI (Common Public
Radio Interface) link is an interface used to connect the pRRUs (Physical Radio Remote Units) to the
BBU (Baseband Unit). The pRRUs contain the radio modules and antennas, while the BBU contains
the baseband processing unit. The CPRI link allows the BBU to send and receive data from the
pRRUs, enabling them to be combined for RF combination. Sources: [1] Chen, F., and Zhang, Y. "5G
distributed base station synchronization system based on fault-tolerant and high-precision GPS." In
2020 IEEE International Conference on Communications Workshops (ICC Workshops), pp. 1-5, 2020.
https://ieeexplore.ieee.org/document/9160372.
[2] Fan, X., and Zhao, X. "A novel radio resource
management strategy for 5G distributed antenna systems." In 2019 IEEE International Conference on
Communications Workshops (ICC Workshops), pp. 1-6, 2019.
https://ieeexplore.ieee.org/document/
If the dock of a base station is locked and the base station fails to obtain clock source signals, which
of the following clock states is the base station in?
B
Explanation:
The base station is in a Holdover state when the dock of a base station is locked and the base station
fails to obtain clock source signals. Holdover is a state during which the base station uses the last
known frequency and time information to maintain synchronization and clock accuracy. According to
the Huawei official documentation, "when the clock source is lost, the base station enters the
holdover state. In the holdover state, the base station uses the last known frequency and time
information to maintain synchronization and clock accuracy. Holdover time is the duration for which
the base station can maintain synchronization after the clock source is lost."